The famous Ring Nebula (also catalogued as Messier 57, M57 or NGC 6720) appears in the northern constellation of Lyra. It is a prominent example of a planetary nebula. This is a shell of ionized gas expelled into the surrounding interstellar medium by a red giant star, which was passing through the last stage in its evolution before becoming a white dwarf.
Read more about Ring Nebula: History, Observation, Properties
Famous quotes containing the word ring:
“This is the gospel of labour, ring it, ye bells of the kirk!
The Lord of Love came down from above, to live with the men who work.
This is the rose that He planted, here in the thorn-curst soil:
Heaven is blest with perfect rest, but the blessing of Earth is toil.”
—Henry Van Dyke (1852–1933)